A high-speed TO-CAN optical transmitter assembly and its manufacturing method

Abstract

The present invention provides a high-speed TO-CAN optical transmitter assembly and a method for manufacturing the same, comprising: a TO base 10, a laser diode 20, a ceramic substrate 30, a transition block 40, a photodetector 50, and a TO cap 60, wherein the ceramic substrate 30 is mounted on the TO base 10, the laser diode 20 is mounted on the ceramic substrate 30, the transition block 40 is mounted on the TO base 10, the photodetector 50 is mounted on the transition block 40, and the TO cap 60 is mounted on the TO base 10 and cooperates with the TO base 10 to form an airtight package. While retaining the advantages of a traditional coaxial packaging structure, the present invention can meet the application requirements of high-speed transmission with a transmission rate of 50Gbps or higher, reducing the complexity of the production process and the cost of production. Furthermore, the present invention can improve the precision matching of the impedance matching circuit and the convenience of maintenance, thereby expanding the application range of the optical transmitter assembly.

Description

Technical Field

[0001] The present invention relates to the technical field of optical transmission components for optical communication systems, and in particular to a high-speed TO-CAN optical transmission component and a manufacturing method thereof. Background Art

[0002] In modern fiber-optic communications, optical transmitter components are an indispensable and important component of optoelectronic conversion modules. Currently, coaxial optical transmitter components based on TO packaging (Transistor Outline-CAN, coaxial packaging) are widely used in fronthaul optoelectronic conversion modules due to their low manufacturing cost and mature and simple process.

[0003] With the advancement of 5G construction and the continuous surge in network throughput, high-frequency transmission rates and compact size have become the mainstream demand trends in the field of optical transmitter components used in optical communication systems. At the same time, the single-wavelength transmission rate requirement for 5G fronthaul networks has also increased from 10Gbps and 25Gbps to 50Gbps (PAM4). Traditional coaxial packaging structures experience significant optical signal reflection when used at transmission rates above 50Gbps. This reflection increases optical signal transmission loss and reduces optical signal transmission efficiency. This reflection is caused by impedance mismatch in the optical transmitter component. Due to the limited space of coaxial optical transmitter components based on TO packages, effective impedance matching circuits cannot be configured. Therefore, achieving impedance matching in coaxial packaging structures is quite difficult. Currently, BOX packaging and COB packaging are commonly used to achieve 50Gbps transmission rates. Compared with coaxial packaging, BOX and COB packaging have the disadvantages of high cost and complex process.

[0004] In view of this, how to overcome the defects of the existing technology and solve the above technical problems is a difficult problem to be solved in this technical field. Summary of the Invention

[0005] In response to the shortcomings of the existing technology, the present invention provides a solution to the technical problems that when traditional coaxial packaging structures are used at transmission rates above 50Gbps, optical signal reflection is significant, optical signal transmission loss is large, transmission efficiency is reduced, and impedance matching circuits cannot be effectively set.

[0006] In order to solve the above technical problems, the present invention adopts the following technical solutions to achieve the above technical objectives:

[0007] In a first aspect, the present invention provides a high-speed TO-CAN optical transmitter assembly, comprising:

[0008] A TO base 10, a laser diode 20, a ceramic substrate 30, a transition block 40, a photodetector 50, and a TO cap 60. The ceramic substrate 30 is mounted on the TO base 10, the laser diode 20 is mounted on the ceramic substrate 30, the transition block 40 is mounted on the TO base 10 and is located below the back-light-emitting surface of the laser diode 20, the photodetector 50 is mounted on the transition block 40 and is used to monitor the optical power of the laser diode 20, the TO cap 60 is mounted on the TO base 10 and cooperates with the TO base 10 to form an airtight package, and the laser diode 20, the ceramic substrate 30, the transition block 40, and the photodetector 50 are respectively located inside the airtight package;

[0009] Among them, the ceramic substrate 30 includes a ceramic substrate base material 301, a first microstrip line 302, a microstrip thin film resistor 303 and a second microstrip line 304. The first microstrip line 302 and the second microstrip line 304 are respectively arranged on the ceramic substrate base material 301. The microstrip thin film resistor 303 is connected in series with the second microstrip line 304. The microstrip thin film resistor 303 is used to achieve impedance matching of the high-frequency signal of the laser diode 20.

[0010] Preferably, the TO base 10 includes a first pin 101, a second pin 102, a third pin 103, a fourth pin 104 and a fifth pin 105, wherein the fifth pin 105 is provided on the symmetry axis of the TO base 10, wherein the locking grooves on the TO base 10 are also symmetrically distributed on both sides of the symmetry axis; the first pin 101 and the second pin 102 are symmetrically arranged about the symmetry axis, and the third pin 103 and the fourth pin 104 are symmetrically arranged about the symmetry axis; the first pin 101 is electrically connected to one end of the first microstrip line 302, and the second pin 102 is electrically connected to one end of the second microstrip line 304; wherein the other end of the first microstrip line 302 and the other end of the second microstrip line 304 are respectively connected to the two poles of the laser diode 20, thereby providing the laser diode 20 with a high-frequency electrical signal;

[0011] The third pin 103 and the fourth pin 104 serve as signal output pins of the photodetector 50 ; the fifth pin 105 serves as a ground pin.

[0012] Preferably, the diameter of the first pin 101 is the same as the diameter of the second pin 102 , and the diameter of the third pin 103 , the diameter of the fourth pin 104 and the diameter of the fifth pin 105 are the same.

[0013] Preferably, the first pin 101 , the second pin 102 , the third pin 103 and the fourth pin 104 are respectively coupled to the TO base 10 through locking grooves on the TO base 10 .

[0014] Preferably, the TO base 10 further includes a glass material 106 , and the glass material 106 is used to fill the space between the first pin 101 and the TO base 10 , and the space between the second pin 102 and the TO base 10 .

[0015] Preferably, the first microstrip line 302 and the second microstrip line 304 are respectively provided with rounded chamfers on their outer contours.

[0016] Preferably, the resistance of the microstrip thin film resistor 303 is 8 to 14 ohms.

[0017] Preferably, the microstrip thin film resistor 303 is composed of a circular insulating substrate and 6 sub-resistors, including a first sub-resistor 3031, a second sub-resistor 3032, a third sub-resistor 3033, a fourth sub-resistor 3034, a fifth sub-resistor 3035 and a sixth sub-resistor 3036;

[0018] The first sub-resistor 3031, the second sub-resistor 3032, the third sub-resistor 3033, the fourth sub-resistor 3034, the fifth sub-resistor 3035, and the sixth sub-resistor 3036 form a pattern structure that radiates from the center of the circular insulating substrate at 60° intervals toward the edge of the circular insulating substrate. One end of the six sub-resistors achieves electrical communication through the center of the circular insulating substrate, and the other ends of the six sub-resistors correspond to six pads on the edge of the circular insulating substrate.

[0019] The second microstrip line 304 is composed of a first portion 3041 and a second portion 3042. After installation, the first portion 3041 and the second portion 3042 are respectively located on both sides of the circular insulating substrate. The adjacent surfaces of the first portion 3041 and the second portion 3042 and the circular insulating substrate are respectively processed into arc-shaped surfaces and coupled with the outer contour of the circular insulating substrate to ensure that the coupling gap is less than or equal to 50 μm.

[0020] The first portion 3041 and the second portion 3042 are each provided with two soldering pads, which are used to complete soldering with four corresponding sub-resistors in the circular insulating substrate; impedance matching is achieved with the laser diode 20 by selecting four different sub-resistors.

[0021] Preferably, the six sub-resistors are obtained by photolithographically sputtering and growing a conductive material on the circular insulating substrate; wherein the resistance values ​​of the six sub-resistors are determined by the length and / or width of the sputtered conductive material.

[0022] In a second aspect, the present invention provides a method for using a high-speed TO-CAN optical transmitter assembly, comprising:

[0023] The ceramic substrate 30 is mounted on the TO base 10; wherein the ceramic substrate 30 includes a microstrip thin film resistor 303, and the microstrip thin film resistor 303 is used to optimize the impedance mismatch caused by the laser diode 20 and absorb high-frequency reflected signals;

[0024] Mounting the laser diode 20 on the ceramic substrate 30;

[0025] The transition block 40 is mounted on the TO base 10 and is located below the back-light emitting surface of the laser diode 20;

[0026] The photodetector 50 is mounted on the transition block 40 and is used to monitor the output light power of the laser diode 20;

[0027] The TO cap 60 is mounted on the TO base 10 and cooperates with the TO base 10 to form an airtight package; wherein the laser diode 20, the ceramic substrate 30, the transition block 40 and the photodetector 50 are respectively located inside the airtight package.

[0028] Compared with the prior art, the above technical solutions adopted by the present invention have the following beneficial effects:

[0029] While retaining the traditional coaxial packaging structure, the present invention uses microstrip thin-film resistors arranged on the microstrip lines of the ceramic substrate to absorb high-frequency reflections caused by impedance mismatch after the laser diode gold wire bonding, thereby improving the modulation frequency of the optical transmission component so that it can meet the application requirements of high-speed transmission above 50Gbps transmission rate. Compared with the BOX packaging and COB packaging currently commonly used for transmission rates above 50Gbps, the complexity of the production process and the production cost are reduced.

[0030] Furthermore, the present invention solves the problem that the impedance matching circuit cannot be adjusted once it is set by setting the microstrip thin film resistor as an adjustable structure, thereby improving the accuracy of the impedance matching circuit and expanding the application range of the optical transmission component. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0032] Figure 1 This is a schematic diagram of the traditional TO-CAN optoelectronic component structure;

[0033] Figure 2 This is a schematic structural diagram of a high-speed TO-CAN optical transmitter assembly provided in Example 1 of the present invention;

[0034] Figure 3 This is a bottom view of a high-speed TO-CAN optical transmitter assembly structure provided in Example 1 of the present invention;

[0035] Figure 4 This is a diagram showing electromagnetic simulation results of a high-speed TO-CAN optical transmitter assembly provided in Example 1 of the present invention;

[0036] Figure 5 This is the eye diagram simulation result of the traditional TO-CAN optoelectronic component applied to the 50Gbps optical communication system;

[0037] Figure 6 This is an eye diagram simulation result diagram of a high-speed TO-CAN optical transmitter structure provided by Example 1 of the present invention applied to a 50Gbps optical communication system;

[0038] Figure 7 This is a schematic diagram of a microstrip thin film resistor structure of a high-speed TO-CAN optical transmitter component provided by Example 2 of the present invention;

[0039] Figure 8 This is a flow chart of a method for manufacturing a high-speed TO-CAN optical transmitter assembly provided by Example 3 of the present invention. In the accompanying drawings, the same reference numerals are used to represent the same components or structures, wherein:

[0040] 10-TO base, 101-first pin, 102-second pin, 103-third pin, 104-fourth pin, 105-fifth pin, 106-glass material; 20-laser diode; 30-ceramic substrate, 301-ceramic substrate base material, 302-first microstrip line, 303-microstrip thin film resistor, 3031-first resistor, 3032-second resistor, 3033-third resistor, 3034-fourth resistor, 3035-fifth resistor, 3036-sixth resistor, 304-second microstrip line, 3041-first part, 3042-second part; 40-transition block; 50-photodetector; 60-TO cap. DETAILED DESCRIPTION

[0041] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts shall fall within the scope of protection of the present invention.

[0042] In the description of the present invention, the terms "inside", "outside", "longitudinal", "lateral", "upper", "lower", "top", "bottom", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present invention and do not require that the present invention must be constructed and operated in a specific orientation. Therefore, they should not be understood as limitations on the present invention.

[0043] In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0044] Example 1:

[0045] In order to meet the application requirements of high-speed transmission above 50Gbps transmission rate, and to reduce and alleviate the technical problems such as high cost and complex process brought by the BOX packaging and COB packaging currently commonly used for transmission rates above 50Gbps, it is necessary to retain the overall technical advantages of the traditional coaxial packaging structure while making it meet the application requirements of high-speed transmission above 50Gbps transmission rate.

[0046] Aiming at the defects of high frequency transmission loss and the like of the traditional coaxial packaging structure, this embodiment 1 provides a high-speed TO-CAN optical transmitter component, such as Figure 2As shown, it includes: a TO base 10, a laser diode 20, a ceramic substrate 30, a transition block 40, a photodetector 50 and a TO cap 60, wherein the ceramic substrate 30 is mounted on the TO base 10, the laser diode 20 is mounted on the ceramic substrate 30, the transition block 40 is mounted on the TO base 10 and is located below the back-light-emitting surface of the laser diode 20, the photodetector 50 is mounted on the transition block 40 and is used to monitor the light output power of the laser diode 20, the TO cap 60 is mounted on the TO base 10 and cooperates with the TO base 10 to form an airtight package, the laser diode 20, the ceramic substrate 30, the transition block 40 and the photodetector 50 0 are respectively located inside the airtight package; in this embodiment, the TO base 10 mainly plays the role of fixed support and electrical connection, and provides a direct or indirect fixing and connection platform for the laser diode 20, the ceramic substrate 30, the transition block 40, the photodetector 50 and the TO cap 60. The ceramic substrate 30, the transition block 40 and the TO cap 60 are basic connection parts. The ceramic substrate 30, the transition block 40 and the TO cap 60 are directly physically connected to the TO base 10 respectively. In specific implementation, 7um Au70Sn30 solder is prefabricated on the back of the ceramic substrate 30 and mounted on the TO base 10 using a eutectic welding process. The transition block 40 is mounted on the TO base 10 through a ring The TO cap 60 is bonded to the TO base 10 by an oxygen glue process, and the TO cap 60 is connected to the TO base 10 by a resistance welding process. The central axis of the TO cap 60 can be consistent with the light-emitting axis of the laser diode 20, or an eccentric cap can be made according to specific coupling requirements. The TO cap 60 can be a flat window cap, a spherical lens cap, or an aspherical lens cap; the laser diode 20 and the photodetector 50 are photoelectric conversion parts, the laser diode 20 is mounted on the ceramic substrate 30, and the photodetector 50 is mounted on the transition block 40. The laser diode 20 and the photodetector 50 are respectively indirectly electrically connected to the TO base 10. When specifically implemented, the laser diode 20 The eutectic welding process is adopted to mount on the ceramic substrate 30. Preferably, the light-emitting axis of the laser diode 20 coincides with the central axis of the TO base 10. The photodetector 50 is bonded to the transition block 40 by a conductive epoxy adhesive process. The photodetector 50 is located directly below the light-emitting surface of the laser diode 20 facing away from the light-emitting surface. Preferably, the angle between the central axis of the photodetector 50 and the light-emitting axis of the laser diode 20 is 6 to 12 degrees. Compared with traditional BOX packaging and COB packaging, TO coaxial packaging technology is relatively mature, simple, and has low implementation cost. However, when applied to high-speed transmission scenarios with a transmission rate of more than 50Gbps, the traditional coaxial packaging structure cannot fully meet the actual application requirements. Figure 1The figure shows the structure of the traditional TO-CAN optoelectronic component. The traditional TO-CAN optoelectronic component has significant optical signal reflection phenomenon and serious optical signal transmission loss. Figure 1 Correspondingly, such as Figure 5 Figure 2 shows the eye diagram simulation results of a traditional TO-CAN optoelectronic component applied to a 50Gbps optical communication system. When the traditional TO-CAN optoelectronic component is applied to a 50Gbps optical communication system, the eye diagram has a small opening and obvious eye diagram jitter, and its overall performance indicators are relatively poor.

[0047] In order to overcome the shortcomings of TO coaxial packaging when applied to high-speed transmission scenarios with a transmission rate of more than 50Gbps, further, the size of the ceramic substrate 30 is preferably 2.8*1.32mm, and the ceramic substrate 30 includes a ceramic substrate base material 301, a first microstrip line 302, a microstrip thin film resistor 303 and a second microstrip line 304. The first microstrip line 302 and the second microstrip line 304 are respectively arranged on the ceramic substrate base material 301, and the microstrip thin film resistor 303 is connected in series with the second microstrip line 304. The microstrip thin film resistor 303 is used to achieve impedance matching of the high-frequency signal of the laser diode 20. When the laser diode 20 is mounted on the ceramic substrate 30, specifically, the cathode of the laser diode 20 is mounted using a eutectic welding process. On the microstrip line 302, at the same time, the positive electrode of the laser diode 20 is connected to the right part of the microstrip line 302 using a 25um gold wire lead. In order to reduce the parasitic inductance caused by the gold wire, when the microstrip line 302 is connected to the positive electrode of the laser diode 20, the length of the microstrip line 302 is controlled within 450um as much as possible. In addition, considering the heat dissipation, CTE and radio frequency characteristics, the ceramic substrate base material 301 is preferably aluminum nitride ceramic. The microstrip line 302 is arranged on the front side of the ceramic substrate 30. The microstrip line 302 is designed with a single-ended 25 ohm impedance. Its metallization layers are Ti = 0.1um, Pt = 0.2um, Au = 0.5um in sequence, and the total thickness tolerance is ±20%. In order to reduce signal reflection during high-frequency transmission, it is preferred that Figure 2As shown, the first microstrip line 302 and the second microstrip line 304 are respectively provided with rounded chamfers on their outer contours, and the microstrip thin film resistor 303 is arranged on the right side of the microstrip line 302. The microstrip thin film resistor 303 is manufactured by sputtering TaN or CrSi process and seamlessly connected to the microstrip line 302. Preferably, when the microstrip line 302 is seamlessly connected to the microstrip line 302, the length of the microstrip line 302 is controlled as much as possible between 100um and 150um. When set, the microstrip line 302 is set at the P pole of the laser diode 20 and as close to the laser diode 20 as possible to optimize the impedance mismatch caused by the positive gold wire connection point of the laser diode 20 and absorb high-frequency reflected signals. Preferably, the outer contour of the microstrip thin film resistor 303 is consistent with that of the microstrip line 302. In this embodiment, the resistance of the microstrip thin film resistor 303 is 8 to 14 ohms.

[0048] It should be noted that in the process of implementing the above connection method, the matching impedance value, the length of the gold wire lead and the length of the microstrip line 302 affect each other and together constitute an impedance value within a reasonable range, ultimately achieving impedance matching. Under the premise of achieving impedance matching, the optical transmission component provided in this embodiment can effectively reduce the possibility of the optical signal being reflected back to the optical transmission end, and can completely transmit the optical signal emitted by the optical transmission end to the target end, thereby improving the integrity and transmission efficiency of the optical signal during transmission and reducing the loss during optical signal transmission.

[0049] In order to realize the electrical connection between the laser diode 20 and the photodetector 50 and the TO base 10, as shown in FIG. Figure 3 As shown, the TO base 10 includes a first pin 101, a second pin 102, a third pin 103, a fourth pin 104 and a fifth pin 105. The fifth pin 105 is arranged on the symmetry axis of the TO base 10. Figure 3As shown, assuming that the axis of symmetry is p, wherein the locking grooves on the TO base 10 are also symmetrically distributed on both sides of the axis of symmetry; the first pin 101 and the second pin 102 are symmetrically arranged about the axis of symmetry, and the third pin 103 and the fourth pin 104 are symmetrically arranged about the axis of symmetry; the first pin 101 is electrically connected to one end of the first microstrip line 302, and the second pin 102 is electrically connected to one end of the second microstrip line 304; wherein the other end of the first microstrip line 302 and the other end of the second microstrip line 304 are respectively connected to the two poles of the laser diode 20, thereby providing a high-frequency electrical signal to the laser diode 20; the third pin 103 and the fourth pin 104 serve as the signal output pins of the photodetector 50; the fifth pin 105 serves as the ground pin. In the actual implementation process, the first pin 101, the The second pin 102, the third pin 103 and the fourth pin 104 are respectively coupled to the TO base 10 through the locking grooves on the TO base 10. In this embodiment, the optical emission component has three gold wire leads, one of which is bonded to the positive electrode of the laser diode 20, one of which is bonded to the microstrip line 302 on the ceramic substrate 30, and the remaining gold wire lead is bonded to the negative electrode of the photodetector 50. When the gold wire lead is bonded to the negative electrode of the photodetector 50, specifically, the positive and negative electrodes of the photodetector 50 are connected to the third pin 103 and the fourth pin 104 respectively. The photodetector 50 transmits the detected optical power data of the laser diode 20 to a related visualization circuit, thereby monitoring the optical power of the laser diode 20.

[0050] In order to effectively achieve impedance matching, such as Figure 3 As shown, the diameter of the first pin 101 is the same as the diameter of the second pin 102. Preferably, the diameter of the first pin 101 and the diameter of the second pin 102 are preferably 0.25 mm, and the diameter of the third pin 103, the diameter of the fourth pin 104 and the diameter of the fifth pin 105 are set to be the same. Preferably, the diameter of the third pin 103, the diameter of the fourth pin 104 and the diameter of the fifth pin 105 are preferably 0.35 mm.

[0051] In the process of achieving impedance matching, considering that there is a gap when the first pin 101 and the second pin 102 are respectively coupled with the TO base 10, in order to ensure airtightness and facilitate impedance matching, Figure 2As shown, the TO base 10 further includes a glass material 106, which is used to fill the gap between the first pin 101 and the TO base 10, and the gap between the second pin 102 and the TO base 10. In this embodiment, the gaps between the first pin 101 and the second pin 102 and the TO base 10 are filled and sealed by the glass material 106.

[0052] The following will compare and illustrate the simulation results and measured results of a high-speed TO-CAN optical transmitter assembly structure provided in Example 1 and a traditional TO-CAN optoelectronic assembly structure when applied to a 50 Gbps optical communication system.

[0053] By comparison, it can be seen that Figure 4 As shown, it is a diagram of electromagnetic simulation results of a high-speed TO-CAN optical transmitter provided by Example 1 of the present invention. A high-speed TO-CAN optical transmitter provided by Example 1 ( Figure 2 The insertion loss S21 parameter is significantly improved. Specifically, the frequency can reach 23GHz at a 3dB bandwidth, which can be fully applied to high-speed transmission scenarios with a transmission rate of more than 50Gbps.

[0054] Furthermore, through comparison, we can see that Figure 6 As shown, it is an eye diagram simulation result diagram of a high-speed TO-CAN optical transmitter structure provided in Example 1 applied to a 50Gbps optical communication system. A high-speed TO-CAN optical transmitter structure provided in Example 1 ( Figure 2 When the optical fiber structure is applied to 50Gbps optical communication systems, the eye diagram has a large opening and small eye diagram jitter, and its overall performance indicators are relatively good.

[0055] This embodiment 1 provides a high-speed TO-CAN optical transmitter component. While retaining the traditional coaxial packaging structure, it overcomes the technical problems of the traditional coaxial packaging structure being unable to effectively set up an impedance matching circuit when used at a transmission rate of 50 Gbps or above, resulting in significant optical signal reflection, large optical signal transmission loss, and reduced transmission efficiency. This allows it to meet the application requirements of high-speed transmission at a transmission rate of 50 Gbps or above while greatly reducing its production and R&D costs.

[0056] Example 2:

[0057] The high-speed TO-CAN optical transmitter component provided in Example 1 has relatively high consistency requirements for parts in the same batch. After the impedance matching circuit is set up, it can effectively meet the batch production requirements.

[0058] Taking into account the possible differences in consistency between components from different batches, and the problem that the impedance matching circuit cannot be adjusted once it is set, on the basis of Example 1, in order to solve the problem of impedance mismatch caused by the differences between components from different batches, the precise matching degree and convenience of maintenance of the matching circuit have improved the application range of the optical transmission component. This Example 2 provides a high-speed TO-CAN optical transmission component, which solves the problem that the impedance matching circuit cannot be adjusted once it is set by setting the microstrip thin film resistor as an adjustable structure, solves the problem of impedance mismatch caused by the differences between components from different batches, and improves the application range of the optical transmission component.

[0059] This example 2 provides a high-speed TO-CAN optical transmitter component, wherein the microstrip thin film resistor 303 is an adjustable structure, such as Figure 7 As shown, the microstrip thin film resistor 303 is composed of a circular insulating substrate and 6 sub-resistors, including a first sub-resistor 3031, a second sub-resistor 3032, a third sub-resistor 3033, a fourth sub-resistor 3034, a fifth sub-resistor 3035 and a sixth sub-resistor 3036; the first sub-resistor 3031, the second sub-resistor 3032, the third sub-resistor 3033, the fourth sub-resistor 3034, the fifth sub-resistor 3035 and the sixth sub-resistor 3036 form a graphic structure that diverges from the central area of ​​the circular insulating substrate at 60° intervals to the edge of the circular insulating substrate; one end of the 6 sub-resistors realizes electrical characteristic interconnection through the central area of ​​the circular insulating substrate, and the other ends of the 6 sub-resistors respectively correspond to 6 pads on the edge of the circular insulating substrate; the second microstrip line 304 is composed of a first part 3041 and a second part 3042, wherein, after installation, the The first part 3041 and the second part 3042 are respectively located on both sides of the circular insulating substrate, and the adjacent surfaces of the first part 3041 and the second part 3042 and the circular insulating substrate are respectively processed into arc surfaces and coupled with the outer contour of the circular insulating substrate to ensure that the coupling gap is less than or equal to 50um; wherein, two soldering pads are respectively made on the first part 3041 and the second part 3042, and the combined width of the first part 3041 and the second part 3042 does not exceed 1.2mm, and the soldering pads are used to complete welding with the four corresponding sub-resistors in the circular insulating substrate; impedance matching is achieved with the laser diode 20 by selecting four different sub-resistors. Preferably, in a specific implementation, the six sub-resistors are specifically obtained by photolithographically sputtering and growing a conductive material on the circular insulating substrate; wherein the resistance values ​​of the six sub-resistors are determined by the length and / or width of the sputtered conductive material.

[0060] In this embodiment, every two consecutive resistors among the first resistor 3031, the second resistor 3032, the third resistor 3033, the fourth resistor 3034, the fifth resistor 3035, and the sixth resistor 3036 and the other two consecutive resistors opposite to the two consecutive resistors together constitute a group of resistance values, constituting a total of three groups of combination values. In specific applications, the three groups of combination values ​​include: the first resistor 3031 and the second resistor 3032, and the fourth resistor 3034 and the fifth resistor 3035 together constitute a group of resistance values; or the second resistor 3032 and the third resistor 3033, and the fifth resistor 3035 and the sixth resistor 3036 together constitute a group of resistance values; or the third resistor 3033 and the fourth resistor 3034, and the sixth resistor 3036 and the first resistor 3031 together constitute a group of resistance values. Preferably, the resistance values ​​of the first resistor 3031, the second resistor 3032, the third resistor 3033, the fourth resistor 3034, the fifth resistor 3035 and the sixth resistor 3036 are preferably different from each other, so as to obtain more combination values. When applied to the scenario of high-speed transmission with a transmission rate of 50 Gbps, the three groups of combination values ​​ultimately still satisfy the resistance value of the microstrip thin film resistor 303 between 8 and 14 ohms as described in Example 1. When applied to other scenarios of high-speed transmission with a transmission rate of more than 50 Gbps, or even when applied to scenarios of high-speed transmission with a transmission rate of less than 50 Gbps, the resistance values ​​of the first resistor 3031, the second resistor 3032, the third resistor 3033, the fourth resistor 3034, the fifth resistor 3035 and the sixth resistor 3036 can be configured as needed.

[0061] This embodiment 2 provides a high-speed TO-CAN optical transmitter component. By setting the microstrip thin film resistor as an adjustable structure, it solves the problem that the impedance matching circuit cannot be adjusted once it is set, solves the problem of impedance mismatch caused by differences between components from different batches, improves the accuracy of the impedance matching circuit and the convenience of maintenance, and expands the application range of the optical transmitter component.

[0062] Example 3:

[0063] Based on the same general technical concept of Example 1 and Example 2, on the basis of Example 1 and Example 2, in order to meet the application requirements of high-speed transmission with a transmission rate of 50Gbps or more, and to reduce and alleviate the technical problems such as high cost and complex process brought about by the currently commonly used BOX packaging and COB packaging with a transmission rate of 50Gbps or more, this Example 3 provides a method for using a high-speed TO-CAN optical transmitter assembly, such as Figure 8 Shown, including:

[0064] S100 , mounting the ceramic substrate 30 on the TO base 10 ; wherein the ceramic substrate 30 includes a microstrip thin film resistor 303 , and the microstrip thin film resistor 303 is used to optimize the impedance mismatch caused by the laser diode 20 and absorb high-frequency reflected signals.

[0065] The back of the ceramic substrate 30 is prefabricated with 7um Au70Sn30 solder and mounted on the TO base 10 using a eutectic welding process.

[0066] S200 , mounting the laser diode 20 on the ceramic substrate 30 .

[0067] The laser diode 20 is mounted on the ceramic substrate 30 using a eutectic welding process. Preferably, the light-emitting axis of the laser diode 20 coincides with the central axis of the TO base 10 .

[0068] S300 , installing the transition block 40 on the TO base 10 and below the back-light-emitting surface of the laser diode 20 .

[0069] The transition block 40 is bonded to the TO base 10 by epoxy adhesive process.

[0070] S400 , installing a photodetector 50 on the transition block 40 and used for monitoring the output light power of the laser diode 20 .

[0071] The photodetector 50 is bonded to the transition block 40 by a conductive epoxy adhesive process. The photodetector 50 is located directly below the light-emitting surface of the laser diode 20. Preferably, the angle between the central axis of the photodetector 50 and the light-emitting axis of the laser diode 20 is 6 to 12 degrees.

[0072] S500, installing the TO cap 60 on the TO base 10 and cooperating with the TO base 10 to form an airtight package; wherein the laser diode 20, the ceramic substrate 30, the transition block 40 and the photodetector 50 are respectively located inside the airtight package.

[0073] Among them, the TO cap 60 is connected to the TO base 10 by a resistance welding process. The central axis of the TO cap 60 can be consistent with the light-emitting axis of the laser diode 20, or an eccentric cap can be made according to specific coupling requirements. The TO cap 60 can be a flat window cap, a spherical lens cap, or an aspheric lens cap.

[0074] In summary, the present invention can meet the application requirements of high-speed transmission above 50Gbps transmission rate while retaining the advantages of the traditional coaxial packaging structure, reducing the complexity of the production process and the production cost. Furthermore, the present invention can also improve the accuracy of the impedance matching circuit, thereby enhancing the application scope of the optical transmission component.

[0075] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A high-speed TO-CAN optical transmitter assembly, characterized in that: include: A TO base (10), a laser diode (20), a ceramic substrate (30), a transition block (40), a photodetector (50) and a TO cap (60), wherein the ceramic substrate (30) is mounted on the TO base (10), the laser diode (20) is mounted on the ceramic substrate (30), the transition block (40) is mounted on the TO base (10) and is located below the back-light-emitting surface of the laser diode (20), the photodetector (50) is mounted on the transition block (40) and is used to monitor the light output power of the laser diode (20), the TO cap (60) is mounted on the TO base (10) and cooperates with the TO base (10) to form an airtight package, and the laser diode (20), the ceramic substrate (30), the transition block (40) and the photodetector (50) are respectively located inside the airtight package; The ceramic substrate (30) comprises a ceramic substrate base material (301), a first microstrip line (302), a microstrip thin film resistor (303), and a second microstrip line (304); the first microstrip line (302) and the second microstrip line (304) are respectively arranged on the ceramic substrate base material (301); the microstrip thin film resistor (303) is connected in series to the second microstrip line (304); and the microstrip thin film resistor (303) is used to achieve impedance matching of a high-frequency signal of the laser diode (20); The microstrip thin film resistor (303) is composed of a circular insulating substrate and six sub-resistors, forming a graphic structure that diverges from the central area of ​​the circular insulating substrate to the edge of the circular insulating substrate at 60° intervals; one end of the six sub-resistors realizes electrical characteristic communication through the central area of ​​the circular insulating substrate, and the other ends of the six sub-resistors respectively correspond to six pads on the edge of the circular insulating substrate; the second microstrip line (304) is composed of a first part (3041) and a second part (3042), and the first part (3041) and the second part (3042) are respectively made with two pads, and the pads are used to complete welding with the four sub-resistors corresponding to each other in the circular insulating substrate; impedance matching is achieved with the laser diode (20) by selecting different four sub-resistors.

2. The high-speed TO-CAN optical transmitter assembly according to claim 1, characterized in that: The TO base (10) includes a first pin (101), a second pin (102), a third pin (103), a fourth pin (104) and a fifth pin (105), wherein the fifth pin (105) is arranged on the symmetry axis of the TO base (10), wherein the locking grooves on the TO base (10) are also symmetrically distributed on both sides of the symmetry axis; the first pin (101) and the second pin (102) are symmetrically arranged about the symmetry axis, and the third pin (103) and the fourth pin (104) are symmetrically arranged about the symmetry axis; the first pin (101) is electrically connected to one end of the first microstrip line (302), and the second pin (102) is electrically connected to one end of the second microstrip line (304); wherein the other end of the first microstrip line (302) and the other end of the second microstrip line (304) are respectively connected to the two poles of the laser diode (20), thereby providing a high-frequency electrical signal to the laser diode (20); The third pin (103) and the fourth pin (104) serve as signal output pins of the photodetector (50); and the fifth pin (105) serves as a ground pin.

3. The high-speed TO-CAN optical transmitter assembly according to claim 2, characterized in that: The diameter of the first pin (101) is the same as the diameter of the second pin (102), and the diameter of the third pin (103), the diameter of the fourth pin (104) and the diameter of the fifth pin (105) are the same.

4. The high-speed TO-CAN optical transmitter assembly according to claim 3, characterized in that: The first pin (101), the second pin (102), the third pin (103) and the fourth pin (104) are respectively coupled to the TO base (10) through the locking grooves on the TO base (10).

5. The high-speed TO-CAN optical transmitter assembly according to claim 4, characterized in that: The TO base (10) further includes a glass material (106), and the glass material (106) is used to fill between the first pin (101) and the TO base (10), and between the second pin (102) and the TO base (10).

6. The high-speed TO-CAN optical transmitter assembly according to any one of claims 1 to 5, characterized in that: Circular chamfers are respectively provided on the outer contours of the first microstrip line (302) and the second microstrip line (304).

7. The high-speed TO-CAN optical transmitter assembly according to any one of claims 1 to 5, characterized in that: The resistance of the microstrip thin film resistor (303) is 8 to 14 ohms.

8. The high-speed TO-CAN optical transmitter assembly according to any one of claims 1 to 5, characterized in that: The six sub-resistors include a first sub-resistor (3031), a second sub-resistor (3032), a third sub-resistor (3033), a fourth sub-resistor (3034), a fifth sub-resistor (3035), and a sixth sub-resistor (3036); The first sub-resistor (3031), the second sub-resistor (3032), the third sub-resistor (3033), the fourth sub-resistor (3034), the fifth sub-resistor (3035) and the sixth sub-resistor (3036) form a graphic structure that diverges from the central area of ​​the circular insulating substrate to the edge of the circular insulating substrate at 60° intervals; after installation, the first part (3041) and the second part (3042) are respectively located on both sides of the circular insulating substrate, and the adjacent surfaces of the first part (3041) and the second part (3042) and the circular insulating substrate are respectively processed into arc-shaped surfaces and coupled with the outer contour of the circular insulating substrate to ensure that the coupling gap is less than or equal to 50um.

9. The high-speed TO-CAN optical transmitter assembly according to claim 8, characterized in that: The six sub-resistors are specifically obtained by photolithographically sputtering and growing a conductive material on the circular insulating substrate; wherein the resistance values ​​of the six sub-resistors are determined by the length and / or width of the sputtered conductive material.

10. A method for manufacturing a high-speed TO-CAN optical transmitter assembly, characterized in that: A method for manufacturing a high-speed TO-CAN optical transmitter assembly according to any one of claims 1 to 9 includes: A ceramic substrate (30) is mounted on a TO base (10); wherein the ceramic substrate (30) includes a microstrip thin film resistor (303), and the microstrip thin film resistor (303) is used to optimize the impedance mismatch caused by the laser diode (20) and absorb high-frequency reflected signals; Mounting a laser diode (20) on the ceramic substrate (30); The transition block (40) is mounted on the TO base (10) and is located below the back-light-emitting surface of the laser diode (20); A photodetector (50) is mounted on the transition block (40) and is used to monitor the light output power of the laser diode (20); A TO cap (60) is mounted on the TO base (10) and cooperates with the TO base (10) to form an airtight package; wherein the laser diode (20), the ceramic substrate (30), the transition block (40) and the photodetector (50) are respectively located inside the airtight package.

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